Variable frequency-controlled, zero-voltage switching, current-fed, single-ended DC-to-AC converter with output isolation

A zero-voltage switching (ZVS), current-fed, single-ended DC-to-AC power converter with output isolation, symmetrical AC output voltage and transformer volt-second balance is proposed. Using variable switching frequency control and operating its two active complementary switches at 50% duty ratio, the power converter regulates output power via an LCC resonant link circuit. ZVS is achieved by a resonant circuit mainly formed by the switch parasitic capacitance and transformer magnetizing inductance. Continuous input current and near-sinusoidal output voltage and current result in low electromagnetic interference